0023226: Extend OpenGl_Context to store map of shared GPU resources

[occt.git] / src / OpenGl / OpenGl_TextureBufferArb.cxx

diff --git a/src/OpenGl/OpenGl_TextureBufferArb.cxx b/src/OpenGl/OpenGl_TextureBufferArb.cxx
new file mode 100644 (file)
index 0000000..405b6fd
--- /dev/null
+++ b/src/OpenGl/OpenGl_TextureBufferArb.cxx
@@ -0,0 +1,151 @@
+// Created by: Kirill GAVRILOV
+// Copyright (c) 2012 OPEN CASCADE SAS
+//
+// The content of this file is subject to the Open CASCADE Technology Public
+// License Version 6.5 (the "License"). You may not use the content of this file
+// except in compliance with the License. Please obtain a copy of the License
+// at http://www.opencascade.org and read it completely before using this file.
+//
+// The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
+// main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
+//
+// The Original Code and all software distributed under the License is
+// distributed on an "AS IS" basis, without warranty of any kind, and the
+// Initial Developer hereby disclaims all such warranties, including without
+// limitation, any warranties of merchantability, fitness for a particular
+// purpose or non-infringement. Please see the License for the specific terms
+// and conditions governing the rights and limitations under the License.
+
+#include <OpenGl_TextureBufferArb.hxx>
+
+#include <OpenGl_Context.hxx>
+#include <Standard_Assert.hxx>
+
+IMPLEMENT_STANDARD_HANDLE (OpenGl_TextureBufferArb, OpenGl_VertexBuffer)
+IMPLEMENT_STANDARD_RTTIEXT(OpenGl_TextureBufferArb, OpenGl_VertexBuffer)
+
+// =======================================================================
+// function : OpenGl_TextureBufferArb
+// purpose  :
+// =======================================================================
+OpenGl_TextureBufferArb::OpenGl_TextureBufferArb()
+: OpenGl_VertexBuffer(),
+  myTextureId (NO_TEXTURE),
+  myTexFormat (GL_RGBA32F)
+{
+  //
+}
+
+// =======================================================================
+// function : ~OpenGl_TextureBufferArb
+// purpose  :
+// =======================================================================
+OpenGl_TextureBufferArb::~OpenGl_TextureBufferArb()
+{
+  Release (NULL);
+}
+
+// =======================================================================
+// function : GetTarget
+// purpose  :
+// =======================================================================
+GLenum OpenGl_TextureBufferArb::GetTarget() const
+{
+  return GL_TEXTURE_BUFFER_ARB; // GL_TEXTURE_BUFFER for OpenGL 3.1+
+}
+
+// =======================================================================
+// function : Release
+// purpose  :
+// =======================================================================
+void OpenGl_TextureBufferArb::Release (const OpenGl_Context* theGlCtx)
+{
+  if (myTextureId != NO_TEXTURE)
+  {
+    // application can not handle this case by exception - this is bug in code
+    Standard_ASSERT_RETURN (theGlCtx != NULL,
+      "OpenGl_TextureBufferExt destroyed without GL context! Possible GPU memory leakage...",);
+
+    glDeleteTextures (1, &myTextureId);
+    myTextureId = NO_TEXTURE;
+  }
+  OpenGl_VertexBuffer::Release (theGlCtx);
+}
+
+// =======================================================================
+// function : Create
+// purpose  :
+// =======================================================================
+bool OpenGl_TextureBufferArb::Create (const Handle(OpenGl_Context)& theGlCtx)
+{
+  if (!OpenGl_VertexBuffer::Create (theGlCtx))
+  {
+    return false;
+  }
+
+  if (myTextureId == NO_TEXTURE)
+  {
+    glGenTextures (1, &myTextureId);
+  }
+  return myTextureId != NO_TEXTURE;
+}
+
+// =======================================================================
+// function : Init
+// purpose  :
+// =======================================================================
+bool OpenGl_TextureBufferArb::Init (const Handle(OpenGl_Context)& theGlCtx,
+                                    const GLuint   theComponentsNb,
+                                    const GLsizei  theElemsNb,
+                                    const GLfloat* theData)
+{
+  if (theComponentsNb != 1
+   && theComponentsNb != 2
+   && theComponentsNb != 4)
+  {
+    // unsupported format
+    return false;
+  }
+  else if (!Create (theGlCtx)
+        || !OpenGl_VertexBuffer::Init (theGlCtx, theComponentsNb, theElemsNb, theData))
+  {
+    return false;
+  }
+
+  switch (theComponentsNb)
+  {
+    case 1: myTexFormat = GL_R32F;    break;
+    case 2: myTexFormat = GL_RG32F;   break;
+    //case 3: myTexFormat = GL_RGB32F;  break; // GL_ARB_texture_buffer_object_rgb32
+    case 4: myTexFormat = GL_RGBA32F; break;
+  }
+
+  Bind (theGlCtx);
+  BindTexture (theGlCtx);
+  theGlCtx->arbTBO->glTexBufferARB (GetTarget(), myTexFormat, myBufferId);
+  UnbindTexture (theGlCtx);
+  Unbind (theGlCtx);
+  return true;
+}
+
+// =======================================================================
+// function : BindTexture
+// purpose  :
+// =======================================================================
+void OpenGl_TextureBufferArb::BindTexture (const Handle(OpenGl_Context)& theGlCtx,
+                                           const GLenum theTextureUnit) const
+{
+  theGlCtx->core20->glActiveTexture (theTextureUnit);
+  glBindTexture (GetTarget(), myTextureId);
+}
+
+// =======================================================================
+// function : UnbindTexture
+// purpose  :
+// =======================================================================
+void OpenGl_TextureBufferArb::UnbindTexture (const Handle(OpenGl_Context)& theGlCtx,
+                                             const GLenum theTextureUnit) const
+{
+  theGlCtx->core20->glActiveTexture (theTextureUnit);
+  glBindTexture (GetTarget(), NO_TEXTURE);
+}